|
10 | 10 | * We use a normal (not "reflected", in Williams' terms) CRC, using initial |
11 | 11 | * all-ones register contents and a final bit inversion. |
12 | 12 | * |
13 | | - * The 64-bit variant is not used as of PostgreSQL 8.1, but we retain the |
14 | | - * code for possible future use. |
15 | | - * |
16 | 13 | * |
17 | 14 | * Portions Copyright (c) 1996-2014, PostgreSQL Global Development Group |
18 | 15 | * Portions Copyright (c) 1994, Regents of the University of California |
@@ -56,97 +53,4 @@ do { \ |
56 | 53 | /* Constant table for CRC calculation */ |
57 | 54 | externCRCDLLIMPORTconstuint32pg_crc32_table[]; |
58 | 55 |
|
59 | | - |
60 | | -#ifdefPROVIDE_64BIT_CRC |
61 | | - |
62 | | -/* |
63 | | - * If we use a 64-bit integer type, then a 64-bit CRC looks just like the |
64 | | - * usual sort of implementation. However, we can also fake it with two |
65 | | - * 32-bit registers. Experience has shown that the two-32-bit-registers code |
66 | | - * is as fast as, or even much faster than, the 64-bit code on all but true |
67 | | - * 64-bit machines. We use SIZEOF_VOID_P to check the native word width. |
68 | | - */ |
69 | | - |
70 | | -#ifSIZEOF_VOID_P<8 |
71 | | - |
72 | | -/* |
73 | | - * crc0 represents the LSBs of the 64-bit value, crc1 the MSBs. Note that |
74 | | - * with crc0 placed first, the output of 32-bit and 64-bit implementations |
75 | | - * will be bit-compatible only on little-endian architectures. If it were |
76 | | - * important to make the two possible implementations bit-compatible on |
77 | | - * all machines, we could do a configure test to decide how to order the |
78 | | - * two fields, but it seems not worth the trouble. |
79 | | - */ |
80 | | -typedefstructpg_crc64 |
81 | | -{ |
82 | | -uint32crc0; |
83 | | -uint32crc1; |
84 | | -}pg_crc64; |
85 | | - |
86 | | -/* Initialize a CRC accumulator */ |
87 | | -#defineINIT_CRC64(crc) ((crc).crc0 = 0xffffffff, (crc).crc1 = 0xffffffff) |
88 | | - |
89 | | -/* Finish a CRC calculation */ |
90 | | -#defineFIN_CRC64(crc)((crc).crc0 ^= 0xffffffff, (crc).crc1 ^= 0xffffffff) |
91 | | - |
92 | | -/* Accumulate some (more) bytes into a CRC */ |
93 | | -#defineCOMP_CRC64(crc,data,len)\ |
94 | | -do { \ |
95 | | -uint32__crc0 = (crc).crc0; \ |
96 | | -uint32__crc1 = (crc).crc1; \ |
97 | | -unsigned char *__data = (unsigned char *) (data); \ |
98 | | -uint32__len = (len); \ |
99 | | -\ |
100 | | -while (__len-- > 0) \ |
101 | | -{ \ |
102 | | -int__tab_index = ((int) (__crc1 >> 24) ^ *__data++) & 0xFF; \ |
103 | | -__crc1 = pg_crc64_table1[__tab_index] ^ ((__crc1 << 8) | (__crc0 >> 24)); \ |
104 | | -__crc0 = pg_crc64_table0[__tab_index] ^ (__crc0 << 8); \ |
105 | | -} \ |
106 | | -(crc).crc0 = __crc0; \ |
107 | | -(crc).crc1 = __crc1; \ |
108 | | -} while (0) |
109 | | - |
110 | | -/* Check for equality of two CRCs */ |
111 | | -#defineEQ_CRC64(c1,c2) ((c1).crc0 == (c2).crc0 && (c1).crc1 == (c2).crc1) |
112 | | - |
113 | | -/* Constant table for CRC calculation */ |
114 | | -externCRCDLLIMPORTconstuint32pg_crc64_table0[]; |
115 | | -externCRCDLLIMPORTconstuint32pg_crc64_table1[]; |
116 | | -#else/* use int64 implementation */ |
117 | | - |
118 | | -typedefstructpg_crc64 |
119 | | -{ |
120 | | -uint64crc0; |
121 | | -}pg_crc64; |
122 | | - |
123 | | -/* Initialize a CRC accumulator */ |
124 | | -#defineINIT_CRC64(crc) ((crc).crc0 = UINT64CONST(0xffffffffffffffff)) |
125 | | - |
126 | | -/* Finish a CRC calculation */ |
127 | | -#defineFIN_CRC64(crc)((crc).crc0 ^= UINT64CONST(0xffffffffffffffff)) |
128 | | - |
129 | | -/* Accumulate some (more) bytes into a CRC */ |
130 | | -#defineCOMP_CRC64(crc,data,len)\ |
131 | | -do { \ |
132 | | -uint64__crc0 = (crc).crc0; \ |
133 | | -unsigned char *__data = (unsigned char *) (data); \ |
134 | | -uint32__len = (len); \ |
135 | | -\ |
136 | | -while (__len-- > 0) \ |
137 | | -{ \ |
138 | | -int__tab_index = ((int) (__crc0 >> 56) ^ *__data++) & 0xFF; \ |
139 | | -__crc0 = pg_crc64_table[__tab_index] ^ (__crc0 << 8); \ |
140 | | -} \ |
141 | | -(crc).crc0 = __crc0; \ |
142 | | -} while (0) |
143 | | - |
144 | | -/* Check for equality of two CRCs */ |
145 | | -#defineEQ_CRC64(c1,c2) ((c1).crc0 == (c2).crc0) |
146 | | - |
147 | | -/* Constant table for CRC calculation */ |
148 | | -externCRCDLLIMPORTconstuint64pg_crc64_table[]; |
149 | | -#endif/* SIZEOF_VOID_P < 8 */ |
150 | | -#endif/* PROVIDE_64BIT_CRC */ |
151 | | - |
152 | 56 | #endif/* PG_CRC_H */ |